1. Technical Field.
This invention relates to the general technical field of exercise equipment and machines and to the more specific technical field of mechanically operated resistance exercise machines designed to strengthen certain leg muscles and muscle groups.
2. Prior Art.
Exercise equipment and machines are available in various configurations and for various purposes. Generally, exercise equipment and machines can be categorized into three broad categories: free weights, mechanically operated resistance machines, and electrically operated resistance machines. Mechanically operated resistance machines can be subcategorized into three broad categories: stack weight resistance operated, free weight resistance operated, and alternative resistance operated. Mechanically operated resistance machines are available for exercising and strengthening various individual muscles, muscle groups and combinations of muscle groups.
Exercise equipment and machines for exercising and strengthening the leg muscles commonly are called leg presses. There are two typical types of leg presses. The first typical leg press has a push plate that can move relative to a frame supporting a stationary seat or other user supporting means. The second typical leg press has a seat or other user supporting means that can move relative to a frame supporting a stationary push plate. Both types of leg presses can operate using a weight stack, free weights, user body weight or other resistance means to supply the desired amount of resistance for exercising the desired leg muscle or muscles.
In the first typical leg press, when the user pushes the push plate forward, the plate either travels on a linear path or, if hinged or pivoted, an arcuate path. Both linear and arcuate paths can induce incorrect biomechanical movement of the user's muscular-skeletal system, thereby causing undesirable stress in various areas of the user's body. In the second typical leg press, when the user pushes against the push plate, the seat or other user supporting means travels in a linear path. As already discussed, such a linear path can induce incorrect biomechanical movement of the user's body, resulting in undesirable stress in various areas of the user's body.
U.S. Pat. No. 4,149,714 to Lambert, Jr. discloses a seated weight lifting leg press exercise machine having a moving push plate and a stationary seat. Lambert '714 is a typical example of a mechanical leg press using weight stacks. The user sits on the seat, bends his knees and places his feet on the push plate, and pushes the push plate by straightening his legs. The push plate travels in an arcuate path and is mechanically connected to a weight stack that can be adjusted to a desired weight. A variable radius cam causes the resistance from the weights to increase during the latter phase of the exercise.
U.S. Pat. No. 4,828,254 to Maag discloses a crank and slider/four-bar variable resistance carriage-type leg press machine having a stationary push plate and a moving seat. Maag '254 is an atypical example of a mechanical leg press using free weights. The user stands on the push plate, bends her knees and places her back against a pad and her shoulders against shoulder pads, and pushes the shoulder pads by straightening her legs. The shoulder pads travel in a linear direction and are mechanically connected to a weight bar that can carry a desired amount of weight. A four-bar linkage causes the resistance from the weights to change during the course of the exercise.
U.S. Pat. No. 5,106,080 to Jones discloses a leg press exercise machine having a stationary seat and two moving push plates, one for each leg. Jones '080 is a typical example of a mechanical leg press using free weights. The user sits on the seat, bends his knees and places each of his feet on one of the push plates, and pushes each push plate by straightening his respective legs. The push plates travel in arcuate paths and each comprise a weight bar that can carry a desired amount of weight. Separate push plates allow independent exercise of each leg.
U.S. Pat. No. 5,366,432 to Habing et al. discloses a leg press having a stationary seat and a moving push plate. Habing '432 is a typical example of a mechanical leg press using a weight stack. The user sits on the seat, bends her knees and places her feet on the push plate, and pushes the push plate by straightening her legs. The push plate travels in a linear path and is mechanically connected to a weight stack that can be adjusted to a desired weight. A pulley and cable system causes the resistance from the weights to change during the course of the exercise.
U.S. Pat. No. 5,484,365 to Jones et al. discloses a leg press exercise machine having a stationary seat and a moving push plate. Jones '365 is another typical example of a mechanical leg press using a weight stack. The user sits on the seat, bends his knees and places his feet on the push plate, and pushes the push plate by straightening his legs. The push plate travels in an arcuate path and is mechanically connected to a weight stack that can be adjusted to a desired weight. A parallel link system, a pair of weight stacks and a counterweight cause the need for overhead connections between the push plate and the weight stack and eliminate the slack inherent in cable systems.
U.S. Pat. No. 5,554,086 to Habing et al. discloses a leg press exercise apparatus having a stationary push plate and a moving seat. Habing '086 is an atypical example of a mechanical leg press using a weight stack. The user sits on the seat, bends her knees and places her feet on the push plate, and pushes the seat by straightening her legs. The seat travels in an arcuate direction and is mechanically connected to a weight stack that can be adjusted to a desired weight. The Habing '086 device is intended to be an add-on feature for a multi-station exercise machine.
U.S. Pat. No. 5,616,107 to Simonson discloses a method and apparatus for leg press exercise with counterbalance having a stationary seat and a moving push plate. Simonson '107 is another typical example of a mechanical leg press using a weight stack. The user sits on the seat, bends his knees and places his feet on the push plate, and pushes the push plate by straightening his legs. The push plate travels in an arcuate path and is mechanically connected to a weight stack that can be adjusted to a desired weight. A counterweight counterbalances the inherent resistance of the leg press machine over the range of the exercise.
U.S. Pat. No. 5,795,270 to Woods et al. discloses a semi-recumbent arm and leg press and aerobic exercise apparatus having a stationary seat and a moving push plate. Woods '270 is an atypical example of a mechanical press using air resistance. The user sits on the seat, bends her knees and places her feet on the push plate, and pushes the push plate by straightening her legs. Air resistance means are mechanically coupled to the push plate and are actuated by pushing the push plate. The user continuously pushes and releases the push plate, achieving both leg press and aerobic exercise. A similar mechanism also is included for exercising the upper body.
The previously described art comprises a general cross-section of the leg press art as it is today. As can be seen, individual apparatuses have either a stationary seat and a moving push plate or a moving seat and a stationary push plate, but not a combination. Further, individual apparatuses have either a linear travel path or an arcuate travel path, but not a combination or a path that more closely resembles the actual biomechanical path of the human body in motion. Individual apparatuses also either use weight stacks, free weights, user body weight or air resistance, or other single resistance mechanisms, and only a small number of apparatuses combine weight stacks or free weights with the user's body weight.
Thus it can be seen that a leg press exercise machine comprising a combination moving seat and moving push plate, an improved travel path more closely resembling the actual biomechanical path of the human leg in motion, and a combination resistance using weight stacks or free weights and the user's body weight would be useful, novel and not obvious, and a significant improvement over the prior art. It is to such leg press exercise machine that the current invention is directed.